1. Field of the Invention
The present invention relates generally to an optical fiber payout dispenser, and, more particularly, to a flexible fiber payout duct for use with such a dispenser.
2. Description of the Related Art
Certain missiles utilize a quantity of an optical fiber which is dispensed upon launch to maintain a data link between the launch site and the missile throughout all or a portion of the flight. The dispenser at the missile, and also frequently at the launch site, consists of a wound fiber coil or stack which is unwound as the missile moves away from the missile launch site. The optical fiber at all times during its use must be protected from bending, kinking or undue stressing which can result in either damage or destruction of the fiber, or reduction of light signal communication efficiency along the fiber.
In some cases, it is necessary to guide the fiber upon dispense along a path to avoid the missile propulsion gases which can quickly destroy an unprotected fiber. In other cases, it may be necessary to provide safe change in the dispensing direction as in the case of a helicopter, for example, which changes its flight direction after missile launch. One approach to this problem is to provide a smooth inner surface pipe or tubing of appropriate configuration to move the dispensed fiber in the required direction. Since the fiber is being dispensed at a very high rate of speed, redirecting or ducting from a rigid tubing is not completely satisfactory in that it can damage the fiber in one or several of the ways already indicated. Also, even if it were satisfactory where a fixed change in direction is required, it still may not be satisfactory for use in dispensing from a helicopter where there could be a substantial and sudden change in direction of unknown magnitude and direction.
It is therefore desirable to be able to provide ducting of an optical fiber being dispensed which is sufficiently variable to accommodate a relatively rapid change in dispensing direction over a substantial solid angle without damaging the fiber or impairing optical signal transmission efficiency.